core: add searching custom file paths

Author: CMurtagh-LGTM

src/core/iconimageprovider.cpp

@@ -9,6 +9,8 @@
 #include <qsize.h>
 #include <qstring.h>
 
+constexpr std::array<QAnyStringView, 2> ICON_FILETYPES = {"png", "xpm"}; // currently cannot open svg file
+
 QPixmap
 IconImageProvider::requestPixmap(const QString& id, QSize* size, const QSize& requestedSize) {
 	QString iconName;
@@ -19,8 +21,7 @@ IconImageProvider::requestPixmap(const QString& id, QSize* size, const QSize& re
 	if (splitIdx != -1) {
 		iconName = id.sliced(0, splitIdx);
 		path = id.sliced(splitIdx + 6);
-		qWarning() << "Searching custom icon paths is not yet supported. Icon path will be ignored for"
-		           << id;
+		path = QString("/%1/%2").arg(path, iconName.sliced(iconName.lastIndexOf('/') + 1));
 	} else {
 		splitIdx = id.indexOf("?fallback=");
 		if (splitIdx != -1) {
@@ -32,7 +33,13 @@ IconImageProvider::requestPixmap(const QString& id, QSize* size, const QSize& re
 	}
 
 	auto icon = QIcon::fromTheme(iconName);
-	if (icon.isNull()) icon = QIcon::fromTheme(fallbackName);
+	if (icon.isNull() && !fallbackName.isEmpty()) icon = QIcon::fromTheme(fallbackName);
+	if (icon.isNull() && !path.isEmpty()) {
+		for (const auto& iconFiletype : ICON_FILETYPES){
+			icon = QPixmap(QString("%1.%2").arg(path, iconFiletype));
+			if (!icon.isNull()) break;
+		}
+	}
 
 	auto targetSize = requestedSize.isValid() ? requestedSize : QSize(100, 100);
 	if (targetSize.width() == 0 || targetSize.height() == 0) targetSize = QSize(2, 2);